You know Fred would have 720's if he were able to. Lets see how Twinturbo Pete's Z does on the dyno next week. He's got basically the same setup but with 720's instead. As far as the JUN cars... your way off... they run JUN 890cc injectors, as well as their Skyline and 2 Silvia's. Not sure about the other big HP Z's in Japan you mention...but almost every one I've seen over there are using additional fuel injectors using a Greddy Rebic or the HKS version.